
class MyThread extends Thread{
    public void run(){
        while(true){
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                throw new RuntimeException(e);
            }
            System.out.println("hello Thread!");
        }
    }
}
public class Demo1 {
    public static void main(String[] args) throws InterruptedException {
        Thread t = new MyThread();
        t.start();
        while(true){
            Thread.sleep(1000);
            System.out.println("hello main!");
        }
    }
}
